Electromagnetic-coupling dual IC card and IC module

ABSTRACT

An electromagnetic-coupling dual IC card includes an IC module and a plate-like card body. The IC module includes a module substrate having a first surface and a second surface, contact terminals provided on the first surface of the module substrate to be contactable with an external contact-type device, an IC chip having a contact communication function and a contactless communication function and disposed on the second surface, and a first connecting coil provided on the first surface. The plate-like card body includes an antenna sheet embedded therein and has a recess for holding the IC module, the antenna sheet being provided with a coupling coil to be electromagnetically coupled to the first connecting coil, and a main coil connected to the coupling coil to perform contactless communication with an external contactless-type device. The first connecting coil does not overlap with the contact terminals in plan view.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application is a Bypass Continuation of International PatentApplication No. PCT/JP2017/041550, filed on Nov. 17, 2017, which isbased upon and claims the benefit of priority of Japanese PatentApplication No. 2016-224863, filed on Nov. 18, 2016, the entire contentsof all of these are hereby incorporated by reference in theirentireties.

TECHNICAL FIELD

The present invention relates to a dual IC card having both a contactcommunication function and a contactless communication function, and anIC module, and in particular, relates to an electromagnetic-couplingdual IC card in which an antenna sheet having an antenna coil forperforming contactless communication can be electromagnetically coupled,via a coupling coil, to an IC module for performing both of thecommunication functions, and an IC module used for theelectromagnetic-coupling dual IC card.

BACKGROUND ART

Dual IC cards having a contact communication function and a contactlesscommunication function have communication modes that can be usedaccording to desired applications. Thus, dual IC cards have been usedfor various applications. Dual IC cards used in recent years are capableof performing with a power supply and establishing communication throughelectromagnetic coupling between an antenna coil of an IC module joinedto the card body by an insulating adhesive or the like, and an antennacoil embedded in the card body. Such electromagnetic-coupling dual ICcards can reduce or prevent unstable electrical connection between theIC module and the card body. In this regard, if the IC module and thecard body are directly connected via an electrically conductiveconnecting member, such as solder, the connecting member may be brokenwhen the dual IC card is bent, or when the connecting member hasdeteriorated with age.

As such electromagnetic-coupling dual IC cards are capable ofelectrically connecting an IC module to the card body throughelectromagnetic coupling, there are known, for example, the IC cards asdescribed in PTLs 1 and 2.

FIG. 9 is a cross-sectional view illustrating an example of anelectromagnetic-coupling dual IC card based on the conventional art. TheIC module 40 includes contact terminals 45 which are formed on the frontsurface of a substrate 43 (front surface of the card) to serve as acontact interface for an external device for contact communication. TheIC module 40 also includes an IC chip 44 mounted to the back surface ofthe substrate 43, and a connecting coil 41 that is formed around the ICchip 44 to provide transformer coupling (electromagnetic coupling).

The card body 50 includes an antenna substrate 42 that is a sheet-likeresin substrate having a first surface provided with a coupling coil 48and an antenna coil (main coil) 49 both of which are formed by printingand resin-sealed. The coupling coil 48 is looped around the outside ofthe IC chip 44 of the IC module 40 in plan view to surround the IC chip44. Between the antenna coil 49 and the coupling coil 48, a capacitor 46is serially connected. The capacitor 46 has an electrode, which is on afirst surface of the antenna substrate 42, connected to an end of theantenna coil 49, and another electrode, which is on the other surface,connected to an end of the coupling coil 48 via a through hole (notshown) provided to the antenna substrate 42.

The coupling coil 48 of the card body 50 is transformer-coupled with theconnecting coil 41 of the IC module 40 to enable power supply andcommunication between the antenna coil 49 and an external device forcontactless communication, such as a reader/writer.

In an application that needs reliability and security, such as anapplication exchanging massive amounts of data or making communicationfor account settlement information with a credit card, contactcommunication is generally used. In an application using a smalleramount of data, such as an application of controlling a gate for entryand exit where the main communication is authentication, contactlesscommunication is generally used.

CITATION LIST

[Patent Literature] [PTL 1] WO 99/26195; [PTL 2] WO 96/35190

SUMMARY OF THE INVENTION

The IC modules of the electromagnetic-coupling dual IC cards asmentioned above may impair communication properties due to reactionmagnetic flux or the like caused by eddy current which is generated byinteraction of the connecting coil with the contact terminals.

Furthermore, in the electromagnetic-coupling dual IC cards as mentionedabove, the number of turns of the connecting coil of the IC module andthe number of turns of the coupling coil of the card body are adjustedto achieve impedance matching and optimize power supply to the IC chipand communication properties. However, the location of the coupling coilin the card body is limited because the location of the IC modulerelative to the card body is prescribed by a standard (JIS X6320-2: 2009(ISO/IEC 7816: 2007)) or the card body needs to be provided with anembossing area (e.g., JIS X6302-1: 2005 (ISO/IEC 7811-1: 2002)) enablingembossing. Therefore, it is not always easy to achieve impedancematching by adjusting the location of the coupling coil.

In addition, IC chips to be mounted to IC modules are produced based onvarious specifications, depending on the size or input capacity requiredof the IC chips. Therefore, it is necessary to adjust the number ofturns or the location of the connecting coil of the IC module inconformity with the required size or input capacity. However, theelectromagnetic-coupling dual IC cards as mentioned above have an arealimitation in the surface where the IC chip is mounted. Therefore, it isnot always easy to adjust the number of turns or the location of theconnecting coil.

The present invention has been made in light of the issues set forthabove, and has an object of providing an electromagnetic-coupling dualIC card that can reduce or prevent degradation of communicationproperties due to reaction magnetic flux or the like caused by eddycurrent which is generated by interaction of the connecting coil withthe contact terminals.

Moreover, the present invention has an object of providing anelectromagnetic-coupling dual IC card that can raise the degree offreedom in the location or the number of turns of the connecting coil ofthe IC module to raise the degree of freedom in achieving impedancematching on the IC module side, and can easily optimize power supply andcommunication properties.

Moreover, the present invention has an object of providing anelectromagnetic-coupling dual IC card that can miniaturize the IC moduleand can be produced at low cost.

[Attempted Improvement or Solution to Problem]

An electromagnetic-coupling dual IC card according to an aspect of thepresent invention includes an IC module and a plate-like card body. TheIC module includes a module substrate having a first surface and asecond surface, contact terminals provided on the first surface of themodule substrate so as to be contactable with an external contact-typedevice, an IC chip having a contact communication function and acontactless communication function and disposed on the second surface ofthe module substrate, and a first connecting coil provided on the firstsurface of the module substrate. The plate-like card body includes anantenna sheet which is embedded therein and has a recess for holding theIC module, the antenna sheet being provided with an antenna having acoupling coil to be electromagnetically coupled to the first connectingcoil, and a main coil connected to the coupling coil to performcontactless communication with an external contactless-type device. Inthis IC card, the first connecting coil is disposed so as not to overlapwith the contact terminals in plan view.

The IC module may further include a second connecting coil provided onthe second surface of the module substrate.

The second connecting coil may be disposed so as not to overlap with thecontact terminals in plan view.

The first connecting coil provided to the first surface may be formed,surrounding the contact terminals in plan view.

The first connecting coil provided to the first surface may besurrounded by the contact terminals in plan view.

The first connecting coil provided to the first surface may be formed,surrounding part of the contact terminals in plan view.

The first connecting coil provided to the first surface may be sealedwith a resin.

An IC module according to an aspect of the present invention includes: amodule substrate having a first surface and a second surface; contactterminals provided on the first surface of the module substrate so as tobe contactable with an external contact-type device; an IC chip having acontact communication function and a contactless communication functionand disposed on the second surface of the module substrate; and a firstconnecting coil provided on the first surface of the module substrate.In the IC module, the first connecting coil is disposed so as not tooverlap with the contact terminals in plan view.

[Desired Advantageous Effects of the Invention]

According to some of the aspects described above, there can be providedan electromagnetic-coupling dual IC card that can reduce or preventdegradation of communication properties due to reaction magnetic flux orthe like caused by eddy current which is generated by interaction of theconnecting coil with the contact terminals.

According to some of the aspects described above, there can be providedan electromagnetic-coupling dual IC card that can raise the degree offreedom in the number of turns or the location of the connecting coil ofthe IC module, and can achieve good impedance matching in conformitywith the size and performance of the IC chip.

According to some of the aspects described above, the IC module can beminiaturized, and thus there can be provided an electromagnetic-couplingdual IC card that can be produced at low cost, and can raise the degreeof freedom in the design of the ticket surface.

According to some of the aspects described above, there can be providedan electromagnetic-coupling dual IC card of higher durability that canprevent breakage of the coil provided to the front surface of the card.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic cross-sectional view illustrating anelectromagnetic-coupling dual IC card, according to an embodiment of thepresent invention.

FIG. 2 is a plan view illustrating an antenna that presents anelectromagnetic-coupling dual IC card, according to an embodiment of thepresent invention.

FIG. 3 is a plan view illustrating an electromagnetic-coupling dual ICcard, according to an embodiment of the present invention.

FIG. 4 is a plan view illustrating an IC module, according to anembodiment of the present invention.

FIG. 5 is a plan view illustrating an IC module, according to anotherembodiment of the present invention.

FIG. 6 is a schematic cross-sectional view illustrating anelectromagnetic-coupling dual IC card, according to another embodimentof the present invention.

FIG. 7 is a plan view illustrating an IC module, according to anotherembodiment of the present invention.

FIG. 8 is a plan view illustrating an IC module, according to anotherembodiment of the present invention.

FIG. 9 is a schematic cross-sectional view illustrating anelectromagnetic-coupling dual IC card based on conventional art.

DESCRIPTION OF THE REPRESENTATIVE EMBODIMENTS

With reference to FIGS. 1 to 4, an electromagnetic-coupling dual IC cardaccording to an embodiment of the present invention will be described.The preferred embodiments of the present invention will now be describedin detail with reference to the drawings. The present invention is notlimited to the following representative embodiments, and appropriatemodifications can be made without departing from the spirit of thepresent invention. The representative embodiments described below aremerely examples of the present invention, and the design thereof couldbe appropriately changed by one skilled in the art. The same constituentelements are denoted by the same reference numerals unless there is areason for the sake of convenience, and redundant description isomitted. In the drawings referred to in the following description, forclarity, characteristic parts are enlarged, and thus the components arenot shown to scale.

FIGS. 1 and 2 show an electromagnetic-coupling dual IC card 1 (may alsobe simply termed IC card 1 hereinafter) according to the presentembodiment which includes a plate-like card body 10 provided with arecess 11, and an IC module 30 held in the recess 11.

FIG. 1 is a schematic cross-sectional view illustrating the dual IC card1. In the figure, the number of turns of an antenna 13, described later,is shown in simplified form. FIG. 2 shows a contour of an antenna sheet12 incorporated in the card body 10, and an example of an arrangement ofthe antenna 13 and a capacitor 14, which are provided to the antennasheet 12.

The card body 10 includes the antenna sheet 12 having the antenna 13,the capacitors 14 electrically connected to the antenna 13, and a cardsubstrate 15 sealing the antenna sheet 12, the antenna 13, and thecapacitor 14.

In the example shown in FIG. 2, the antenna sheet 12 is formed into arectangular shape in plan view. As materials for the antenna sheet 12,for example, PET (polyethylene terephthalate), polyethylene naphthalate(PEN), and the like, having insulation properties may be mentioned.

The antenna sheet 12 has a short side 12 c near which a holding hole 12d is formed, passing through the antenna sheet 12 in a thicknessdirection D thereof. The holding hole 12 d is formed into a rectangularshape, in plan view, with its sides being parallel to short or longsides of the antenna sheet 12. The antenna sheet 12 has a thickness, forexample, in the range of 15 μm to 50 μm.

The antenna 13 has a coupling coil 18 electromagnetically coupled to asecond connecting coil 31 and a first connecting coil 36 of the ICmodule 30, described later, and a main coil 19 connected to the couplingcoil 18 to perform contactless communication with an externalcontactless-type device (not shown), such as a reader/writer. In theexample shown in FIG. 2, the coupling coil 18 is disposed in an area R1,and the main coil 19 is disposed in an area R2 adjacent to the area R1.

At a position between the holding hole 12 and a long side 12 e of theantenna sheet 12, there is provided an embossing area R3 enablingembossing based on IC card standard (X 6302-1: 2005 (ISO/IEC 7811-1:2002)).

In the example shown in FIGS. 2 and 3, the coupling coil 18 is spirallyformed on a first surface 12 a of the antenna sheet 12, where the recess11 is open. More specifically, the coupling coil 18 with five turns isprovided around the IC module 30 (recess 11) in plan view (i.e. asviewed from above the IC card 1 along a line normal to the front surfacethereof). The coupling coil 18 in the embossing area R3 is configured byan element wire 18 a, while the coupling coil 18 on the outside of theembossing area R3 is configured by an element wire 18 b. The elementwire 18 a has a width larger than that of the element wire 18 b. Theelement wire 18 b has an innermost end provided with a substantiallycircular terminal 20 having a width larger than that of the element wire18 b. The terminal 20 is formed on the first surface 12 a.

A substantially circular terminal 22 is provided, overlapping with theterminal 20 of the coupling coil 18 in the thickness direction D. Theterminal 22 is connected to the capacitor 14 via a connecting wire 21.The terminal 20 of the coupling coil 18 is electrically connected to theterminal 22 of the connecting wire 21 by using known crimping processingor the like. The capacitor 14 is serially connected between the couplingcoil 18 and the main coil 19.

As shown in FIG. 2, the main coil 19 is formed in the area R2, beingspirally looped three times. The main coil in the embossing area R3 isconfigured by an element wire 19 a, while the main coil 19 on theoutside of the embossing area R3 is configured by an element wire 19 b.The element wire 19 a has a width larger than that of the element wire19 b. By increasing the width of the element wire 19 a and the width ofthe element wire 18 a, the element wires 19 a and 18 a can be preventedfrom being disconnected when the embossing area R3 is embossed.

The element wire 19 a of the main coil 19 has an outermost end connectedto the outermost end of the element wire 18 a of the coupling coil 18.

The element wires 19 b and 18 b each have a width, for example, in therange of about 0.1 mm to 1 mm. By arranging each of the element wires 19b and 18 b at an interval in the range of about 0.1 mm to 1 mm betweenturns, the coupling coil 18 and the main coil 19 in the areas other thanthe area R3 can be formed. However, the width and the arrangementinterval of the element wires 19 b and 18 b are not limited to thesevalues. The element wires 19 a and 18 b each have a width, for example,in the range of about 1 mm to 15 mm. By arranging each of the elementwires 19 a and 18 a at an interval in the range of about 0.1 mm to 1 mmbetween turns, the coupling coil 18 and the main coil 19 in theembossing area R3 can be formed. However, the width and the arrangementinterval of the element wires 19 a and 18 a are not limited to thesevalues.

As shown in FIGS. 1 and 2, the capacitor 14 has an electrode plate 14 aprovided on the first surface 12 a of the antenna sheet 12, and anelectrode plate 14 b provided on a second surface 12 b of the antennasheet 12. The electrode plates 14 a and 14 b are disposed face-to-face,sandwiching the antenna sheet 12.

The electrode plate 14 a is connected to the innermost end of theelement wire 19 b of the main coil 19.

The electrode plate 14 b is connected to the connecting wire 21 providedto the second surface 12 b. As mentioned above, the connecting wire 21is connected to the terminal 22.

The antenna 13, the capacitor 14, and the connecting wire 21 are formed,for example, by generally used gravure printing, i.e., by etching acopper foil or an aluminum foil to which a resist is applied.

As can be seen from the example shown in FIG. 3, the card substrate 15is formed into a rectangular shape in plan view. Examples of thematerial for the card substrate 15 include insulating materials,including polyester-based materials such as amorphous polyester, vinylchloride-based materials such as PVC (polyvinyl chloride),polycarbonate-based materials, and PET-G (polyethylene terephthalatecopolymer).

As shown in FIG. 1, the recess 11 is formed in the card substrate 15.The recess 11 has a first holder 24 that is open in the front surface ofthe card substrate 15, and a second holder 25 communicating with thefirst holder 24 and having a width smaller than that of the first holder24.

It should be noted that the card body 10 may be formed by sandwiching aseparately prepared antenna sheet 12, antenna 13, and capacitor 14between a pair of films, and integrating the pair of films by laminationthrough hot pressing or by using an adhesive, followed by punching theintegrated material into a card shape.

As shown in FIG. 1, the IC module 30 includes a sheet-like modulesubstrate 33 having a second surface 33 b and a first surface 33 a, anIC chip 34 and a second connecting coil 31 which are provided to thesecond surface 33 b of the module substrate 33, and a first connectingcoil 36 and a plurality of contact terminals (contact terminals) 35which are provided to the first surface 33 a of the module substrate 33.The IC module 30 may further include a resin seal 39.

The module substrate 33 is formed into a rectangular shape in plan view.As the material for the module substrate 33, for example, glass epoxy,PET (polyethylene terephthalate), or the like may be mentioned. Themodule substrate 33 has a thickness, for example, in the range of 50 μmto 200 μm.

As the IC chip 34, a known IC chip having a contact communicationfunction and a contactless communication function may be used.

The second connecting coil 31 is spirally formed on the second surface33 b of the module substrate 33 so as to surround the IC chip 34 and theresin seal 39. The first connecting coil 36 is spirally formed on thefirst surface 33 a of the module substrate 33 so as to surround theplurality of contact terminals 35. The second connecting coil 31 isdisposed so as not to overlap with the plurality of contact terminals 35in plan view. The term “in plan view” refers to a view from above the ICmodule 33 along a line normal to the surface 33 a (33 b).

The first connecting coil 36 has end points 37 and 38 respectivelyprovided with through holes 37 c and 38 c passing through the modulesubstrate 33. These through holes 37 c and 38 c respectively includemetal layers which are formed by a known plating technique, or othertechniques. The end point 37, which is on the first surface 33 a, iselectrically connected to the second connecting coil 31 on the secondsurface 33 b via the through hole 37 c. The end point 38, which is alsoon the first surface 33 a, is electrically connected to the IC chip 34on the second surface 33 b via the through hole 38 c.

The first connecting coil 36 is disposed so as not to overlap with theplurality of contact terminals 35 in plan view. In the example shown inFIG. 1, the second and first connecting coils 31 and 36 are held in thefirst holder 24 of the recess 11, and disposed between the side wall ofthe first holder 24 and the side wall of the second holder 25.

The second and first connecting coils 31 and 36 are each formed, forexample, by etching a copper foil or an aluminum foil. The second andfirst connecting coils 31 and 36 each have a thickness, for example, inthe range of 5 μm to 50 μm. The first connecting coil 36 may be plated,with plating wires 60 being connected thereto.

The second and first connecting coils 31 and 36 configure contactlessterminals which can be electromagnetically coupled to the coupling coil18 of the card body 10.

The contact terminals 35 are formed, for example, by laminating a copperfoil, which has a predetermined pattern, on the first surface 33 a ofthe module substrate 33. Portions of the copper foil exposed externallymay be provided with a nickel layer by plating, with a thickness in therange of 0.5 μm to 3 μm. The nickel film may further be provided thereonwith a gold layer by plating, with a thickness in the range of 0.01 μmto 0.3 μm. The plurality of contact terminals 35, as C1 to C7, may beplated, with plating wires 60 being connected thereto. When the firstconnecting coil 36 surround the plurality of contact terminals 35, as C1to C7, on the first surface 33 a, the plating wires 60 may be providedon the second surface 33 b and connected to the contact terminals 35 viarespective plating through holes 60 c.

The contact terminals 35 are used for communicating with an externalcontact-type device, such as an automatic teller machine. The contactterminals 35 are connected to an element or the like, not shown,incorporated in the IC chip 34.

It should be noted that non-electrolytic plating may be conductedinstead of electrolytic plating that involves use of the plating wires60. The same applies to the following description of plating.

The second connecting coil 31 has an end which is connected to the ICchip 34 through a wire, not shown, and has the other end which isconnected, as mentioned above, to an end of the first connecting coil 36via the through hole 37 c. The other end of the first connecting coil 36is connected to the IC chip 34 through a wire, not shown, via thethrough hole 38 c. The IC chip 34, the second and first connecting coils31 and 36, and the wires altogether configure a closed circuit.

Although the connecting coils 31 and 36 are respectively provided to thesecond and first surfaces 33 b and 33 a of the module substrate 33 inthe example shown in FIG. 1, the second connecting coil 31 may beomitted, from the perspective of alleviating the influence of eddycurrent described later (see FIG. 4).

The resin seal 39 may be formed, for example, of a known epoxy resin orthe like. With the resin seal 39 being provided to the IC module 30, theIC chip 34 can be protected, or wire disconnection can be prevented fromoccurring.

As described above, the electromagnetic-coupling dual IC card 1 isprovided with the connecting coil 36 on the first surface 33 a of themodule substrate 33 so as not to overlap with the contact terminals 35in plan view. Thus, communication properties are prevented from beingdegraded due to reaction magnetic flux or the like caused by eddycurrent which is generated by interaction of the connecting coil withthe contact terminals. Accordingly, an electromagnetic-coupling dual ICcard 1 having good communication properties can be obtained.

In this regard, an IC card having a connecting coil, which is providedoverlapping with the contact terminals in plan view, allows increase ofeddy current generated in the contact terminals which are formed ofmetal sheets. Increase of eddy current accelerates energy loss andgeneration of reaction magnetic flux, resultantly attenuating thesignal-carrying magnetic flux used for communication. Consequently,adequate communication properties are not necessarily obtained.

When the module substrate 33 is provided with the second and firstconnecting coils 31 and 36 on the respective surfaces thereof, thenumber of turns of the coil on one surface of the module substrate 33can be reduced to obtain an inductance which is equivalent to theinductance of a module substrate provided with a connecting coil on onesurface thereof. Specifically, the space occupied by the connectingcoils in the module substrate 33 in plan view can be reduced. In otherwords, there are fewer limitations in the arrangement or the number ofturns of the connecting coils. Accordingly, impedance matching is easilyachieved with the coupling coil 18 of the card body 10. With thisconfiguration, IC chips having different impedance properties can bereliably dealt with. Even when a plurality of types of IC chips areused, communication properties or performance, such as power supply, canbe easily optimized.

Taking an example of using one IC chip, the IC module, which isconfigured to include a module substrate with a connecting coil formedon only one surface, is required to have a size of about 11.8 mm×13.0 mmin order to accomplish communication properties that meet ISO standardsor the like. In this regard, the IC module, which is configured toinclude a module substrate with connecting coils formed on bothsurfaces, only needs to have a size of about 8.32 mm×11.0 mm in order toaccomplish communication properties that can meet such standards. Inthis way, the IC module 30 can be miniaturized, and the module substrate33 can be produced at lower cost. Thus, a less expensiveelectromagnetic-coupling dual IC card can be provided.

In addition, miniaturization of the IC module 30 leads to increase inarea for arranging motifs on the ticket surface of the IC card 1, andthus further leads to improving designability of the card.

The contact terminals 35 and the first connecting coil 36 formed on thefirst surface 33 a of the module substrate 33 may be covered with aresin, such as epoxy, for protection.

In this case, the first connecting coil 36, which is formed on the samesurface as are the contact terminals 35 of the IC module 30, isprevented from being broken due to wear caused by being brought intocontact with the contact terminals of a contact-type reader/writer.Specifically, an electromagnetic-coupling dual IC card having higherdurability can be obtained for use with a contact-type reader/writer.

An embodiment of the present invention has so far been described indetail with reference to the drawings. However, specific configurationsare not limited to this embodiment. The present invention shouldencompass modifications, combinations, or the like of this embodiment,in the range not departing from the spirit of the present invention. Forexample, as shown in FIG. 4, the first connecting coil 36 may beprovided surrounding the plurality of contact terminals 35 (C1 to C7)provided on the first surface 33 a of the module substrate 33. In thiscase, since the first connecting coil 36 does not overlap with theplurality of contact terminals 35, the influence of eddy current can bealleviated. As shown in FIGS. 5 and 6, the first connecting coil 36 ofthe IC module 30 may be looped in a space surrounded by the plurality ofcontact terminals 35 provided on the first surface 33 a of the modulesubstrate 33. Furthermore, the second connecting coil 31 may be providedto the second surface 33 b of the module substrate 33 (omitted from FIG.5).

As shown in FIG. 7, the first connecting coil 36 may be provided,surrounding some of the plurality of contact terminals 35 (only C1 toC3). In these cases, the connecting coil can be provided in a smallspace on the outside of the contact terminals, which is beneficial tominiaturization of the IC module. In particular, the IC module 30 shownin FIG. 5 can substantially dispense with the space for providing theconnecting coil on the outside of the contact terminals 35, as C1 to C7,and is even more beneficial to miniaturization of the IC module.

It is preferable that there is only a small overlap, in plan view,between the second connecting coil 31 on the second surface 33 b, andthe contact terminals 35 on the first surface 33 a. A smaller overlapcan accordingly even better alleviate the influence of eddy current.From the perspective of alleviating the influence of eddy current, it ismost preferable that, as shown in FIG. 1 and FIG. 8 (referred to later),neither of the first and second connecting coils 36 and 31 overlaps withthe contact terminals 35 on the first surface 33 a in plan view.

In the module 30 shown in FIG. 5, the plating wires 60 can be connectedto the plurality of contact terminals 35, as C1 to C7, and the firstconnecting coil 36 on the first surface 33 a, without the need ofproviding the plating through holes 60 c. Thus, the process ofconnecting the plating wires 60 can be simplified.

As shown in FIG. 8, in plan view, the first connecting coil 36 may beprovided on the first surface 33 a of the module substrate 33 so as tosurround the plurality of contact terminals 35, as C1 to C7, and thesecond connecting coil 31 may be provided on the second surface 33 b ofthe module substrate 33 so as to be looped on the inward side of theplurality of contact terminals 35, as C1 to C7. In this example, thesecond and first connecting coils 31 and 36 are both disposed so as notto overlap, in plan view, with the contact terminals 35.

In this example, the second connecting coil 31 disposed on the secondsurface 33 b has two end points 37′ and 38′. The end point 37′ isconnected to the end point 37 of the first connecting coil 36 on thefirst surface 33 a via the through hole 37 c (37′c). The end point 38′is electrically connected to the IC chip 34. It should be noted that theplurality of contact terminals 35, as C1 to C7, and the first connectingcoil 36 may be plated in the same manner as described above.

In the example shown in FIG. 8, the second connecting coil 31 may partlyoverlap with the IC chip 34 in plan view. In other words, the IC chip 34may be disposed so as to partly overlap with the second connecting coil31 disposed on the second surface 33 b.

Hereinafter, a method of producing the electromagnetic-coupling dual ICcard 1 will be described by way of an example.

1. Card Substrate

There is prepared a card substrate 15 made of a material, such aspolyvinyl chloride (PVC) or polyethylene terephthalate copolymer(PET-G), having insulation properties or durability required ofgenerally used card substrates.

2. IC Module

There is prepared an IC module 30 which is equipped with an IC chip 34having both of contact and contactless communication functions, andincludes contact terminals 35 used for contact communication, andconnecting coils (31, 36) used for contactless communication andestablishing communication with and supplying power to the coupling coil18 of the card body 10.

The contact terminals 35 and the connecting coil 36 (31) are formed of aplurality of copper foil patterns which are formed by etching a surfaceof an insulating substrate made such as of glass epoxy or PET and havinga thickness in the range of 50 μm to 200 μm. The copper foil patternshave exposed portions which are nickel-plated with a thickness in therange of 0.5 μm to 3 μm, and further gold-plated thereon with athickness in the range of 0.01 μm to 0.3 μm. However, the platingconfiguration is not limited to this.

3. IC Chip

The IC chip 34 is adhered to glass epoxy or PET by a die attachmentadhesive, and directly bonded to external connecting terminals and theconnecting coils (31, 36) through gold or copper wires, each having asize in the range of ϕ10 μm to ϕ40 μm, or bonded to patterns, which areconnected to the external connecting terminals and the connecting coils(31, 36), through holes opened in the glass epoxy or PET.

4. Antenna Sheet

As an antenna circuit for performing contactless communication, there isprepared an antenna sheet 12 including a main coil 19 for communicatingwith a reader/writer, a coupling coil 18 for transformer-coupling withthe connecting coil 36 (31) of the IC module 30, and a capacitor 14. Theantenna circuit is formed by patterning a material of a copper foil oran aluminum foil with a thickness in the range of 5 μm to 50 μm byetching on the front and back surfaces of an insulating base substratesuch as of polyethylene terephthalate (PET) or polyethylene naphthalate(PEN) with a thickness of 15 μm to 50 μm.

5. Forming

The antenna sheet 12 is sandwiched between two card substrates 15 forlamination with hot pressing, or for adhesion processing or the like toobtain an integrated body. The integrated body is then punched into acard shape to form a card body 10.

6. Milling

The card body 10 is milled to form a recess 11 (cavity) for embeddingthe module 30.

7. Adhesion

The IC module 30 is mounted to the recess 11 (cavity) of the card body10 by use of an adhesive, such as a hot melt sheet, thereby obtaining anelectromagnetic-coupling dual IC card 1.

INDUSTRIAL APPLICABILITY

According to the embodiment described above, there can be provided anelectromagnetic-coupling dual IC card that can reduce or preventdegradation of communication properties due to reaction magnetic flux orthe like caused by eddy current which is generated by interaction of theconnecting coil with the contact terminals.

REFERENCE SIGNS LIST

1 . . . Electromagnetic-coupling dual IC card; 10 . . . Card body; 11 .. . Recess; 12 . . . Antenna sheet; 13 . . . Antenna; 14 . . .Capacitor; 15 . . . Card substrate; 18 . . . Coupling coil; 19 . . .Main coil; 20 . . . Terminal; 21 . . . Connecting wire; 22 . . .Terminal; 24 . . . First holder; 25 . . . Second holder; 30 . . . ICmodule; 31 . . . First connecting coil; 33 . . . Module substrate; 4 . .. IC chip; 35 . . . Contact terminal; 36 . . . Second connecting coil;37, 38 . . . End point; 39 . . . Resin seal.

What is claimed is:
 1. An electromagnetic-coupling dual IC cardcomprising: an IC module that includes a module substrate having a firstsurface and a second surface, a plurality of contact terminals providedon the first surface of the module substrate so as to be contactablewith an external contact-type device, an IC chip having a contactcommunication function and a contactless communication function anddisposed on the second surface of the module substrate, and a firstconnecting coil provided on the first surface of the module substrate;and a card body that includes an antenna sheet and has a recess thatholds the IC module, the antenna sheet comprises an antenna having (a) acoupling coil to be electromagnetically coupled to the first connectingcoil, and (b) a main coil connected to the coupling coil to performcontactless communication with an external contactless-type device,wherein the plurality of contact terminals surround the first connectingcoil on the first surface of the module substrate.
 2. Theelectromagnetic-coupling dual IC card of claim 1, wherein the IC modulefurther includes a second connecting coil provided on the second surfaceof the module substrate.
 3. The electromagnetic-coupling dual IC card ofclaim 2, wherein the second connecting coil is disposed so as not tooverlap with the contact terminals in plan view.
 4. Theelectromagnetic-coupling dual IC card of claim 1, wherein the firstconnecting coil provided to the first surface is sealed with a resin. 5.The electromagnetic-coupling dual IC card of claim 1, wherein theantenna sheet, including the coupling coil and the main coil, isembedded into the card body so that the coupling coil and the main coilare surrounded by a material of the card body.